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The eccentric cleavage product of ?-carotene, ?-apo-13-carotenone, functions as an antagonist of RXR?.

ABSTRACT: In this study, we investigated the effects of eccentric cleavage products of ?-carotene, i.e. ?-apocarotenoids (BACs), on retinoid X receptor alpha (RXR?) signaling. Transactivation assays were performed to test whether BACs activate or antagonize RXR?. Reporter gene constructs (RXRE-Luc, pRL-tk) and RXR? were transfected into Cos-1 cells and used to perform these assays. None of the BACs tested activated RXR?. Among the compounds tested, ?-apo-13-carotenone was found to antagonize the activation of RXR? by 9-cis-retinoic acid and was effective at concentrations as low as 1 nM. Molecular modeling studies revealed that ?-apo-13-carotenone makes molecular interactions like an antagonist of RXR?. The results suggest a possible function of BACs on RXR? signaling.

SUBMITTER: Eroglu A

PROVIDER: S-EPMC3517194 | biostudies-literature | 2010 Dec

REPOSITORIES: biostudies-literature

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The eccentric cleavage product of β-carotene, β-apo-13-carotenone, functions as an antagonist of RXRα.

Eroglu Abdulkerim A Hruszkewycz Damian P DP Curley Robert W RW Harrison Earl H EH

Archives of biochemistry and biophysics 20100801 1

In this study, we investigated the effects of eccentric cleavage products of β-carotene, i.e. β-apocarotenoids (BACs), on retinoid X receptor alpha (RXRα) signaling. Transactivation assays were performed to test whether BACs activate or antagonize RXRα. Reporter gene constructs (RXRE-Luc, pRL-tk) and RXRα were transfected into Cos-1 cells and used to perform these assays. None of the BACs tested activated RXRα. Among the compounds tested, β-apo-13-carotenone was found to antagonize the activatio ...[more]

PMID: 20678466

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